Baking composition



. p This invention relates to a baking and relates particularly to a baking powder com- Patented Apr. 24, 195 1 Guy A. McDonald, Chicago Heights, 111., assignor to Victor Chemical W'orks,-a corporation of Illinois No Drawing. Application December 23, 1947,

Serial No. 793,531

14 Claims. (01. 99-95) composition,

position and a self-rising flour composition including a new baking acid. The invention also' relates to a baking composition comprising a new baking acid combined with a modifier or accelerator. V

This application is a continuation-in-part application of my copending application Serial No. 625,442, filed October 29, 1945. This copending application claims specifically the new complex alkali metal-aluminum or iron acid'phosphates disclosed herein.

' Certain alkali metal -aluminum compounds have heretofore been suggested and employed as baking acids, but prior to the present invention they have had the unfortunate property of producing a bitter taste. The present compound,

on-the other hand, produces tasteless products upon reaction with sodium bicarbonate.

Furthermore, as will be shown in detail, the

centrate it sufficiently to cause crystallization, and then cooling. The crystalline product is filtered off and washed with methanol to remove ,down, with agitation, until -the boiling point new material produces carbon dioxide slowly by n the reaction and has a high capacity for producing carbon dioxide. Products, such as biscuits, resulting from the use of this baking acid are,

therefore, light and large in volume.

The new complex has the formula:

. MM'3H14(PO4) s 4H2O wherein M is an alkalimetal including the ammonium radical, and M is a trivalent metal of the class consisting of aluminum and iron.

'In general, the new compounds may be prepared by reacting a reactive trivalent iron or v aluminum compound such as the'metal itself or its hydroxide, etc., with an excess of concentrated phosphoric acid, adding sufiicient alkali metal hydroxide or carbonate to give a ratio of one atom of alkali metal to three atoms of iron or aluminum, heating the solution and boiling to con- 40 their crystal characteristics:

the excess phosphoric acid. The product is in the form of colorless or slightly colored plate-like V hexagonal crystals having the general formula:

where M represents an alkali metal or ammonium aluminum atom.

radical, and M' represents a trivalent iron or The following example illustrates the exact h procedure followed in producing the sodium aluf grams of phosphoric acid at 70 c. The sominum acid phosphate compound.

.108,grams of soda ash was slowly added to 3376 lution was heated to C, and 458 grams of aluminum hydrate added at such rate that the charge did not boil over. The solution was boiled reached about- C. The charge became thick with crystals and was cooled to room temperature while continuing the agitation. The charge was then diluted with about two volumes of a 75% methanol-25% water (by volume) solution and filtered. The crystals were washed with a 75% methanol-water solution and finally with methanol to remove any free phosphoric acid. After drying at 70 C., the product weighed 1400 grams. Analysis of the crystals showed them to correspond to the formula:

NaAI3H14(PO4) s 4H2O Following a similar procedure by substituting .iron for aluminum and by using different alkali metal and ammonium reactants, a number of complex compounds were produced. The following table shows some of these compounds and Compound ype Crystals Axis g g g Hexagonal Plates Biaxial I do (in do {Nm=1- 600 c mmercial Baking tests show that the acidic hydrogen atoms of the molecule react with sodium bicare bonate in baking preparations, liberating a large amount of carbon dioxide gas for leavening purposes substantially in accord with the followe ing equation:

The pr ipal residual salt of the le ve n reaction designated in the above equation by emniricalformulais a comp ex i s luble bas c pho phate, th stru ure of whi h has n b en eiinitely established. The salt, however, is inert and does not give the baked product a bitter taste such. as is norma ly ob a ned w en employ n phosphate-alum type leavenin agents.

The reaction oharacteristios of the new compou ds n baki g procedures ar milar to those of the Well own. sodium a uminum sul ate bakn ac d n t they reac i h od b Donate wly n dough mixtures at ord n y peratures, retaining. a large measure of leaven- Nengm React n B es Ba ng Add ins Value 2 Min. 5 Min.

Cc. Cc. KAI9H14(PO4) M1120- 100. 4 35. 51. 5 NaAl5H14(PO4)a4HzO 102. 0 41. 6 58. 6 NH4Al@H14(PO4)s-4H2O 108.0 31.8 44. 4

From the table it will be observed that approximately 22'to of the theoretical amount of leavening gas is liberated in the dough stage over This characteristic of the compounds The proportions of sodium bicarbonate and baking acids were based on neutralizing values of 80 for (A), 102 for (B) and 100 for (C).

Biscuit bakes were made irom doughs made with the above flours, using 12.0 parts of shortening and 66.2 parts of water based on 100 parts of flour. The following table shows the results of he b kes- Specific volume of biscuit 2.20 3.08 2.7l

pH Value of crumb hn 7.19 7. 62 7.75

Height ofobiscuits "inches" 6% 10% 9% a 15 minute period at room temperature of 27 C. 7

The column headed Neutralizing value represents the amount of sodium bicarbonate re uired by weight to neutralize the acidity of 100 parts by weight of the baking acid.

The following table shows two self-rising flour formulas made up with two of the new baking acids, and for comparison a'formula using ordinary-monocalc um phosphate as the baking id t obtained by either component alone.

acid may be merely a simple mixture.

The doughs for the above biscuits were mixed for 15 seconds in a Hobart dough mixer, rolled out to thickness, folded double, rolled out, folded double at right angles to the first folding, rolled out to original thickness, and circular doughs cut therefrom. They were baked for 15 minutes at 450 F.

The new compounds may be suitabl used in preparing baking powders by admixing sodium bicarbonate andstarch with the new baking acids in proportions to give the desired available CO2 content.

The new product is entirely compatible with monocalcium phosphate and the like and may be used in combinations with other baking acids to give a range of bakin characteristics from the slow action of the new compounds to the fast action of the other baking acids such as hydrated monocalcium phosphate. For example, a baking powder consisting of 28% granular sodium bicarbonate, 13% hydrated monocalcium phosphate, 20% sodium aluminum acid ph sphat (NaAlzHrdPOQalHzO), and 39% corn starch is highly stable, and represents an excellent formula for a commercial type baking powder.

For some purposes, it may be desirable to accelerate the speed of reaction of the new complex. In such cases, an accelerator or modifier maybe added. Th accelerator or modifier is of the phosphate type and may be such materials as monocalcium phosphate or sodium acid pyrophosphate. The added phosphate material does not affect the reaction characteristics of the new complex acid, but the mixture gives a baking acid composition with leavening characteristics between those of the two acids and also results in superior baked products that have improved characteristics over those prepared when either is used alone.

When monocalcium phosphate is used to modify the new complex acid, the monocalcium phosphate causes an early rapid, leavening action, while the new complex acid phosphate contributes its late slow leavening action. The mixture of the monocalcium phosphate and the new complex When such a mixture is used, the combination of the fast and slow acting acids provide a baking result A homogeneous admixture of the monocalcium phosphate and the new complex acid phosphate may be prepared by forming the monocalcium acid composition may be modified with economic advantage by preparing the new compounds as described above up to the step of removing the excess acid with an organic solvent. At this stage, instead of removing the excess phosphoric acid, it may beneutralized with hydratedlime to substantially convert the excess acid into monocalcium phosphate, thus yielding a homogeneous this procedure is as follows:

1440 grams of 560 Be. phosphoric acid was diluted with an equal volume of water and heated to80 C. 145 grams of metallic aluminum was u slowly added and after the reaction subsided, the

mixture was heated at 90-100 C. for several hours. 7 The impurities and excess aluminum were filtered off, and 475 grams of 560 B. phosphoric ing point had reached 122 C. The mixture was then poured into a mixer containing 200 grams of hydrated line. Vigorous agitation was continued until the mixture solidified into small granular lumps. It was then dried for 18 hours at about 95 C. and milled. The product was a dry, non-hygroscopic powder having a neutralizing valve of 100. 1. It was tested in the baking of biscuits and found to have baking characteristics equal to that of standard commercial phosphate-alum baking powders, except that it possessed the distinct advantage over the phosphate-alum baking powder of not producing a bitter astringent taste in the biscuit. Results of baking at a neutralizing value of 90 showed the baked biscuits to have a specific volume of 2.6, a pH value of 7.4, and a fine open grain structure. Excellent results were also obtained with the above new type baking acids in baking cakes and doughnuts.

When the new acid complex phosphate is eombined with sodium acid pyrophosphate a superior composition is also provided. In this case, both the sodium acid pyrophosphate and the new complex acid phosphate are relatively slow baking acids. For example, the reaction rate of the new sodium aluminum acid phosphate at 38 C. is '70 co. in two minutes and 101 cc. in fifteen minutes as compared to 88 cc. and 116 cc. for sodium acid pyrophosphate under the same conditions. In a mixture of equal parts by weight of the two baking acids, the corresponding reaction rates are 80 cc. and 11.3 cc. under the same conditions. Although this reaction rate appears to be very close to what would be expected in such a combination, the use of the mixture in baking preparations results in obtaining improved qualities in the baked goods. For example, in the cooking of doughnuts a better quality product is obtained with mixtures of thetwo acids than with either alone. A typical doughnut formula was prepared with 100 parts flour, '7 parts dried milk solids, 38.2 parts sugar, 4.6 parts powdered egg yolk, 1.16 parts salt, 5.6 parts shortening and 0.4 part spices.- To this mixture were added sodium bicarbonate and baking acids. To the completed mixtures 70 parts of water were added and the materials mixed to form a batter. Standard size doughnut doughs were cut and then fried in deep fat. Tests were made using commercial sodium acid pyrophosphate, the new sodium aluminum acid phosphate, and mixtures of these two baking acids. Using 1.3 parts of sodium bicarbonate per 100 parts of flour in the above formula and amounts of baking acids corresponding to neutralizing values of 70 for sodium acid pyrophosphate, 115 for the sodium aluminum acid phosphate, and for mixtures of equal parts by weight of the two baking acids, a series of doughnuts were prepared havmg the followmg properties:

Sodium Sodium Baking Acid Acid Pyro: Alum. Acid 8 phosphate Phosphate ywelg Spec. Volume ofdoughnut 3.17 3.11. 3.16. Gaininweight, percent (Ab- 9.5 4.6 4.8.

sorption of cooking oil). pH value of crumb- 8.35 8.20 8.45.

very good. very good. excellent. o do Do.

smooth.... sl rough smooth. very good. fine open.. excellent.

.do soft......- Do. sl. bitter. excellent-. Do.

A further test with the 50/50 mixture using 10% less baking acids and sodium bicarbonate gave quality results equivalent to those of the 50/50 mixture in the above table, except that the specific volumewas slightly lower, being 3.05 instead of 3.16.

Using a mixture of 75% sodium aluminum acid phosphate and 25% sodium acid pyrophosphate with a 20% reduction in the leavening ingredients, the doughnut quality was substantially the same as that of the example in the above table where the sodium aluminum acid phosphate was used on a 100% leavening basis, except that the specific volume was reduced to 2.92.

The above quality tests represent the consensus of several observers on unidentified samples, and therefore shows a distinct quality improvement in the use of the mixed baking acids.

The term accelerator or modifier is intended to mean that the combination with the new complex acid phosphate results in faster reaction rates for the mixtures than are obtained when the new complex acid phosphates are used alone.

The foregoing detailed description has been given for clearness of understanding only, and no unnecessary limitations should be understood therefrom.

I claim: 1. A baking powder composition comprising sodium bicarbonate, starch, and a baking acid, a

substantial proportion of which is a complex crystalline compound having the formula:

MlVI3H14(PO4) a 4H2O 3. A baking powder composition as set forth in claim 1 in which the baking acid is a mixture of hydrated monocalcium phosphate and a com pound of the formula NaA13H14(PO4)a 4H2O.

4. A baking powder composition as set forth in claim 1 in which the baking acid is a mixture of sodium acid pyrophosphate and a compound of the formula NaA13Hi4(PO4) a lHzO.

5. A baking powder composition comprising a mixture of approximately 28 parts by weight of sodium bicarbonate, 39 parts corn starch, 13 parts monocalcium phosphate, and 20 parts sodium aluminum acid phosphate having the formula:

7 6- A e irrisins flou co p itio wmpri ne flou al s di m b c bonat and a le venin proportion 91 a baki cid S tan proportion of which is a crystalline compound having the formula:

MMsH14(PO4) s 4H2O wherein M represents a member of the class consisting of sodium potassium and ammonium and M represents a member of the class consisting of aluminum and iron.

7. A self-rising flour composition as set forth in claim 6 in which the baking acid has the ormul 10. A crystalline acidic compound having the formula MM3H14(PO4,) a -4H20 having intimately admixed therewith a substantial proportion of an acid accelerator of the class consisting of hydrated monocalcium phosphate and sodium acid pyrophosphate.

8 1- A com n a se o h la 10 i which the accelerator is hydrated monocalcium phosphate. 12. A compound as set forth in claim 10 which the accelerator is hydrated monocalcium phosphate and the proportion of complex to monocalcium phosphate is approximately 60 to 40.

13. A compound as set forth in claim 10 in which the accelerator is sodium acid pyrophosphate. 14. A compound as set forth in .claim 10 in which the accelerator is sodium acid pyrophosphate and the proportion of complex to the sodium acid pyrophosphate is approximately 50 to 50.

GUY A. M DONALD.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Holbrook Oct. 13, 1914 OTHER REFERENCES Number 

1. A BAKING POWDER COMPOSITION COMPRISING SODIUM BICARBONATE, STARCH, AND A BAKING ACID, A SUBSTANTIAL PROPORTION OF WHICH IS A COMPLEX CRYSTALLINE COMPOUND HAVING THE FORMULA: 